Being captive bred in South America doesn't relate at all to getting permits for the in the US. They US cares about wild populations only. It was pain for me to get them as an AZA governed insitutuion.
Arapaimaman - you say you've kept them in tanks. What size tanks? How long did the fish live? How large did it get?
That picture that Ali posted makes me cry everytime I see it. That fish can't even turn around! That shows a complete lack of respect for the fish keeping hobby.
We should all realize by now that you should be purchasing a fish just for the sake of watching it grow up, then try to dump it because you can't care for it. Or even worse then that, keep it crammed in a smaller area than it needs to live just so you can brag about owning one.
I've said it before, and I'll say it again. I've only seen one private tank that was good enough to house them for a life time. ArapaimaG has it. If someone else were to construct something at that scale, I'd be all for helping them aquire an animal.